Punch through the Height Ceiling

On the level ''Hostage Crisis'' fly right past the hostages and follow the road out. after making one right turn and going almost as far as you can go without turning again, you will see a yellow/orange building on the right side that you can land on, it is lower than the other buildings.

Fly over this building this way and you will go out into forbidden teritory, behind the walls of the city and above the normally enforced ceiling. You can't fly or shoot down into the city though once you are there, because its like an invisible bubble over the city, you just land on it and can walk.

Use Special Armor on Ground Levels

Normally you can only use the special veritech armor (Super Veritech, Armored Veritech, etc.) you can only use them in space missions. However this was overlooked and can be used. Begin a space-mission with the special armor equiped on your veritech, beat the space mission, when the mission is over you can select Continue, you will continue to the next level (or a level you have not beaten yet) with the special veritech armor still equiped!